Objective: To determine whether North American guidelines published subsequent to and in the same topic areas as those developed by the US Agency for Health Care Policy and Research (AHCPR) meet the same methodological criteria.

Study design: A guideline appraisal instrument containing 30 criteria was used to evaluate the methodological quality of the AHCPR guidelines, "updates" of the AHCPR guidelines authored by others, and guidelines that referenced or were adapted from the AHCPR guidelines. The frequency with which the criteria appeared in each guideline was compared and an analysis was performed to determine guidelines with two key features of the ACHPR guidelines—multidisciplinary guideline development panels and systematic reviews of the literature. Data were extracted from the guidelines by one investigator and then checked for accuracy by the other.

Results: Fifty two guidelines identified by broad based searches were evaluated. 50% of the criteria were present in every AHCPR guideline. The AHCPR guidelines scored 80% or more on 24 of the 30 criteria compared with 14 for the "updates" and 11 for those that referenced/adapted the AHCPR guidelines. All of the 17 AHCPR guidelines had both multidisciplinary development panels and systematic reviews of the literature compared with five from the other two categories (p<0.05).

Conclusions: North American guidelines developed subsequent to and in the same topic areas as the AHCPR guidelines are of substantially worse methodological quality and ignore key features important to guideline development. This finding contrasts with previously published conclusions that guideline methodological quality is improving over time.